This invention relates to loading and unloading devices, and more particularly, to a tail gate frame movably attached to a vehicle, wherein the frame receives a pair of air-permeable, foldable ramps to serve either in the folded state as an entire tail gate or in the unfolded state as ramps extending from the tail gate frame for loading wheeled objects onto the vehicle.
Traditionally, people used boards to load wheeled objects into vehicles. This method is unsafe, unreliable and cumbersome.
More recently, there has been provided vehicle tail gates which are capable of also being used as loading ramps. For example, each of U.S. Pat. Nos. 1,639,879 issued to Buffington; 2,603,529 issued to Troth et al.; 2,727,781 issued 'Eath; and 2,797,960 issued to Endres et al., generally discloses a tail gate ramp having at least two sections pivotally connected to form a unitary member. The tail gate is also fixedly and pivotally connected to the floor of the vehicle to allow downward movement to form a ramp.
Unfortunately, the tail gate ramps of the above-discussed patents are very heavy and difficult to use by a single person, thus, increasing the risk of worker injury. In addition, the prior art tail gates' weight and substantially solid construction increases wind resistance, decreases fuel efficiency and decreases rear visibility.
In this latter regard, vehicle tail gates are known which are partially porous to allow some air to pass therethrough. However, these tail gates are not intended to act as ramps for loading or unloading objects.
Traditionally, the objects of a vehicle tail gate which can function as a ramp and be flow-through have been mutually exclusive because a flow-through tailgate almost necessarily lacks the strength and durability required to support the weight of an object being loaded onto a vehicle. For example, even though U.S. Pat. No. 2,603,529 suggests that part of the tail gate can be flow-through to minimize wind resistance, the strength requirements of this patented device necessitate that the majority of the tail gate be made of a solid, heavy material.
In summary, the above-discussed prior art does not teach a vehicle tail gate which functions as a loading ramp, is flow through, is easy to install and use, is strong and durable and yet is relatively inexpensive to manufacture and maintain.